Well, that depends. Materially, it might not be too much, with Martin continuing to serve as Executive Producer on the series while also writing episodes of the series--most of the heavy lifting is done by showrunners David Benioff and D.B. Weiss on that front.

But the deal also allows him to create more programming for the network, opening up the possibility that Martin will be very busy if he's trying to get one or more new series off the ground in the coming years.